Answer:
He failed to check for extraneous solutions
Step-by-step explanation:
sqrt(x+6) -4 =x
Add 4 to each side
sqrt(x+6) -4+4 =x+4
sqrt(x+6) =x+4
Sqaure each side
(sqrt(x+6))^2 =(x+4)^2
x+6 = x^2 +8x+16
Subtract 6 from each side
x = x^2 +8x +10
Subtract x from each side
0 = x^2 +7x +10
Factor
0 = (x+5) (x+2)
Using the zero product property
x=-5 x=-2
Check the solutions
sqrt(-5+6) -4 =-5
sqrt(1) -4 = -5
1-4 =-5
-3 does not equal -5 not a solution
sqrt(-2+6) -4 =-2
sqrt(4) -4 = -2
2-4 =-2 is a solution
Answer:
4 squares
Step-by-step explanation:
If the rectangle is only 3 cm wide, only one square will be able to fit in a row. Since the square is 12 cm long, 4 squares can fit. This can be found by 12/3 which = 4
I think it's $320.1
15x5=75 15x8=120 15x6=90
75x.18=13.5 120x.18=21.6
75+120+90+13.5+21.6=320.1
Check if I did my math correct